Go onto Institutions > Timetable > Timetable Administration > Timetable Slots.
On the Timetable slots page, you are able to take several actions, use the filter panel at the top of the page and filter your timetable slots by subject, course/class or year group. This will help you easily identify lessons that have the same teacher or are in the same room.
Tick the timetable slots that need to have more staff members added onto or removed from, then click on 'Change staff'.
In the slide over, you'll see the option to add an effective date (you can set this to a date in the future if you don't want this change to happen straight away), and a Remove and Add field.
You can select all the staff to remove from this slot and all the staff to add, all at once. Just start typing the names into each box to select them, then click Change Staff.
The staff will then be updated, and the staff member will be able to take the register for this class.
Top Tip: To remove a staff member from all slots, select all of the timetable slots and select Change Staff. Then select the staff to remove.